#pragma once

///顺序栈类型定义
template <typename E, int M>
struct SqStack
{
    E elem[M];
    int top;
};

///顺序栈的基操作
///初始化栈为空 InitStack(&S)
template <typename E, int M>
void InitStack(SqStack<E, M> &S)
{
    S.top = 0;
}

///判断栈是否为空 StackEmpty(S)
template <typename E, int M>
bool StackEmpty(const SqStack<E, M> &S)
{
    return S.top == 0;
}
///入栈 Push(&S,e)
template <typename E, int M>
void Push(SqStack<E, M> &S, E e)
{
    //若栈满，则抛出异常
    if (S.top == M)
        throw "Stack full";
    //否则，入栈
    S.elem[S.top++] = e;
}
///出栈 Pop(&S, &e)
template <typename E, int M>
void Pop(SqStack<E, M> &S, E &e)
{
    //若栈空，则抛出异常
    if (S.top == 0)
        throw "Stack empty";
    //否则，出栈
    e = S.elem[--S.top];
}
///取栈顶元素
template <typename E, int M>
void GetTop(const SqStack<E, M> &S, E &e)
{
    //若栈空，则抛出异常
    if (S.top == 0)
        throw "Stack empty";
    //否则，返回栈顶元素
    e = S.elem[S.top - 1];
}